Since most consumers do not understand today’s highly complex global food system, they are not aware of how the costs of production, processing, storage and transportation affect food prices. That was the conclusion of a 2001 study, “Food, Fuel and Freeways: An Iowa Perspective on How Far Food Travels, Food Usage and Greenhouse Gas Emissions” by Rich Pirog, Timothy Van Pelt, Kamyar Enshayan and Ellen Cook of the Leopold Center for Sustainable Agriculture in Ames, Iowa. The study looked at transportation from farm to point-of-sale within local, regional and conventional food systems.

I would venture to guess that at least one aspect of that conclusion has changed: awareness of how energy costs affect food prices is rising in consumers’ consciousness.

According to the Bureau of Labor Statistics’ Consumer Price Index, energy costs to consumers rose 86.3 percent from 1997 to 2007, compared to 29 percent for food. Seven years after the Leopold Center study, consumers are certainly more aware of how energy costs directly and indirectly affect their household budget. They’ve got their own energy bills and the nightly news to spell it out for them.

The Leopold Center study counts environmental costs as the increased amount of fossil fuel used to transport food long distances, as well as the increase in greenhouse gas emissions resulting from the burning of these fuels. Using fresh produce and other foods as examples, the study considered miles traveled, fossil fuels used and carbon dioxide emissions, and assessed potential environmental costs.

Local and regional food systems, where farmers and processors sell and distribute their food to consumers within a given area, use less fossil fuel for transportation because the distance from farm to consumer is shorter.

The study sampled data from three Iowa local food projects where farmers sold to institutional markets such as hospitals, restaurants and conference centers. The food traveled an average of 44.6 miles to reach its destination, compared with an estimated 1,546 miles if these food items had arrived from conventional national sources.

A common dinner of chuck roast, potatoes, carrots and green beans could travel a collective distance of 5,375 miles through conventional channels before reaching the dinner table, while the same meal grown locally could travel a collective distance of just 90 miles before reaching the dinner table.

The conventional food transportation system used four to 17 times more fuel than the Iowa-based regional and local systems, depending on the system and truck type. The same conventional system released from five to 17 times more CO2 from the burning of this fuel than the Iowa-based regional and local systems.

Put in terms of gallons, the savings seem even more impressive. Growing and transporting 10 percent more of the produce for Iowa consumption in an Iowa-based regional or local food system would result in an annual savings ranging from 280 to 346 thousand gallons of fuel and an annual reduction in CO2 emissions ranging from 6.7 to 7.9 million pounds, depending on the system and truck type.

Here’s a fact that farmers can take to the bank: based on consumption estimates of a selected 28 fruits and vegetables, if an additional 10 percent of these produce items were grown and sold in Iowa, it would result in $54.3 million in sales for Iowa farmers (based on wholesale prices). These dollars would multiply several times in Iowa communities rather than communities in other states or countries.

Now, more than ever, there are compelling reasons to focus farm marketing efforts locally. Marketing directly to consumers, finding local wholesale buyers and distributors, and working the buy local message into advertising and PR materials only makes sense with our current energy issues.

Consumers are now aware of the relationship between energy and food costs. Why not remind them that supporting your farm bolsters a local and regional food system, which benefits them, the environment and the economy?

The author, a freelance writer, is public affairs specialist for the USDA Natural Resources Conservation Service in Amherst, Mass., and was previously director of communications at the Mass. Dept. of Food & Agriculture.